We have been selling this top quality bottom bracket for years and have found none better. This is a true cartridge bearing bottom bracket, with sealed, replaceable bearings. It has a lightweight titanium spindle and an aluminum shell. It also allows a few millimeters of lateral adjustment, which can help fix some shifting and alignment problems. Mounting rings are needed and are sold separately (#0168). ISO taper is for post 1993 Campagnolo and other specific cranks. JIS is for 1993 and earlier Campagnolo, Shimano and most other cranks.